1. Field of the Invention
The present invention relates to a preventive or remedy for hypertension.
2. Description of the Related Art
Cardiac diseases such as angina pectoris, myocardial infarction and heart failure, and cerebrovascular diseases such as cerebral infarction, cerebral hemorrhage and subarachnoid hemorrhage have a close relation to hypertension and they are, respectively, the second and third leading causes of death among Japanese. According to National Livelihood Survey (fiscal 1998) of Health and Welfare Ministry, out of 1000 patients attending a hospital, 64 patients go there for treating hypertension and it is the first leading cause of disease in Japan. For the treatment of hypertension, employed is drug therapy using an antihypertensive such as diuretic, sympatholytic depressant, vasodilator or angiotensin converting enzyme inhibitor. Therapy with such a drug is applied mainly to patients of serious hypertension. General treatment for lifestyle modification including dietetic therapy, therapeutic exercise and cessation of drinking or smoking is, on the other hand, employed for patients at various stages of hypertension from mild hypertension to severe hypertension. Importance of the general treatment has therefore been recognized recently. Of the general treatment, improvement in eating habits is said to be important. There exists a number of foods which have traditionally been said to have an antihypertensive action. In addition, antihypertensive materials derived from foods have been searched extensively, and many active ingredients having an antihypertensive action have been separated or isolated.
Although many of the drugs employed to treat hypertension are satisfactory in their effectiveness, they are not completely free from side effects such as tachycardia and bradycardia and place a heavy burden on patients. Foods which are said to have an antihypertensive action, or active ingredients thereof do not always have satisfactory effectiveness and many of them need enough time to exhibit their antihypertensive effect fully. Recently, the present inventor has found (in Japanese Patent Application No. 2000-107957) that ferulic acid exhibits a high hypertension ameliorating effect while having less side effects. It is however revealed that the antihypertensive effect of ferulic acid does not last long because of its high metabolic rate as measured in vivo.
An object of the present invention is therefore to provide a preventive or remedy for hypertension which has a long lasting antihypertensive effect, has a high degree of safety, does not impose a large stress on patients upon intake of it and has a higher antihypertensive action.